Multiple reactor chemical production system

Abstract

The present invention is a multiple reaction set for the production of chemicals by equilibrium limited reactions utilizing plate-type or extended surface heat exchangers. The heat exchangers effectively cool the reaction products in order to condense the methanol contained within the reaction products for separation, and also to warm incoming feed reactants prior to entrance of the reactants into a reactor utilized for the production of methanol. The various reactors, heat exchangers, and separators can be formed as separated zones within the enclosed vessels, thereby eliminating the need for separately constructed reactors, heat exchangers, and separators. Multi-stream plate-type of extended surface heat exchangers can be utilized to allow efficient cooling and methanol separation. The multiple reaction set can also be used for the recovery of methanol from a waste or purge gas stream utilizing multiple reactors, multiple plate-type or extended surface heat exchangers and multiple separators as a substitute for or in conjunction with a conventional methanol synthesis loop.

1. A product synthesis apparatus for the production of a product formed by an equilibrium-limited reaction, the apparatus comprising:
 a) a reactor vessel adapted to withstand the operating temperatures and pressures of the product-forming reaction, the reactor vessel including a number of reaction zones formed within the reactor vessel by dividing walls extending across the reactor vessel to define the reaction zones, the dividing walls configured to withstand the temperature and pressure differentials across each adjacent reaction zones; 
 b) a separation vessel adapted to withstand the operating temperatures and pressures of the product-forming reaction, the separation vessel including a number of separation zones formed within the separation vessel by dividing walls extending across the separation vessel to define the separation zones, each dividing wall configured to withstand the temperature and pressure differentials across adjacent separation zones; and 
 c) a heat exchanger block including a number of feed/effluent heat exchanger units, each unit operably connected to at least one of the reaction zones and to at least two of the separation zones. 
 
     
     
       2. The apparatus of  claim 1  wherein the reactor vessel is formed as a header for the heat exchanger block. 
     
     
       3. The apparatus of  claim 1  wherein each reaction zone includes an inlet port and an outlet port extending through the reaction vessel and each operably connected to an associated heat exchanger unit in the heat exchanger block. 
     
     
       4. The apparatus of  claim 1  wherein each separation zone includes an inlet opening extending through the separation vessel and operably connected to an upstream heat exchanger unit, a first outlet opening extending through the separation vessel and operably connected to a downstream heat exchanger unit, and a second outlet opening extending through the separation vessel and operably connected to a product collection stream. 
     
     
       5. The apparatus of  claim 1  wherein the heat exchanger block is integrally connected to the separation vessel. 
     
     
       6. The apparatus of  claim 1  wherein the heat exchanger units are selected from the group consisting of brazed fin heat exchangers, printed circuit heat exchangers, diffusion bonded fin and plate heat exchangers, and spiral wound heat exchangers. 
     
     
       7. The apparatus of  claim 1  wherein the product is selected from the group consisting of: methanol, dimethyl ether and mixtures thereof. 
     
     
       8. The apparatus of  claim 1  wherein the feed/effluent heat exchanger units each have an efficiency of at least 5 NTU. 
     
     
       9. The apparatus of  claim 1  wherein the feed/effluent heat exchanger units are each operably connected to a cooling utility stream used to condense the product present within the heat exchanger units. 
     
     
       10. The apparatus of  claim 1  wherein the separation vessel includes a weir system connecting each of the separation zones and forming a product collection stream. 
     
     
       11. A product synthesis apparatus for the production of a product formed by an equilibrium-limited reaction, the apparatus comprising:
 a) a reactor vessel adapted to withstand the operating temperatures and pressures of the product-forming reaction; 
 b) a separation vessel adapted to withstand the operating temperatures and pressures of the product-forming reaction, the separation vessel including a number of separation zones formed within the separation vessel by dividing walls extending across the separation vessel to define the separation zones, each dividing wall configured to withstand the temperature and pressure differentials across adjacent separation zones; and 
 c) a heat exchanger operably connected to the reactor vessel and to at least two of the separation zones, wherein the heat exchanger comprises a feed/effluent heat exchanger unit disposed within each separation zone, each unit also operably connected to a downstream separation zone. 
 
     
     
       12. The apparatus of  claim 11  wherein the feed/effluent heat exchanger units are each operably connected to a cooling utility stream and the heat exchange units are each formed with a first portion for thermally contacting a feed stream with a reaction product stream for the reactor vessel, a second portion downstream from the first portion for thermally contacting the reaction product stream with the cooling utility, and a third portion downstream from the second portion for separating the condensed product from the reaction product stream. 
     
     
       13. A method for the synthesis of a product formed by an equilibrium limited reaction, the method comprising the steps of:
 a) providing the apparatus of  claim 1 ; 
 b) directing a feed stream through the apparatus; and 
 c) recovering a product collection stream from the apparatus. 
 
     
     
       14. The method of  claim 13  wherein the feed stream is a purge gas stream from a recycle stream of a chemical production reactor utilizing a steam or autothermal reformer, and wherein the step of directing the feed stream comprises directing the purge gas stream through the apparatus. 
     
     
       15. The method of  claim 13  wherein the feed stream is a syn-gas created in a steam or autothermal reformer. 
     
     
       16. The method of  claim 13  wherein the step of recovering the product collection stream comprises recovering a product collection stream of less than 2,500 tons per day. 
     
     
       17. The method of  claim 13  wherein the step of recovering the product collection stream comprises recovering a product collection stream of less than 1,500 tons per day. 
     
     
       18. The method of  claim 13  wherein the step of recovering the product collection stream comprises recovering a product collection stream of less than 1,000 tons per day.